Merge branch 'develop-add-fire' of github.com:Unity-Technologies/ml-agents into develop-add-fire-export

ml-agents/mlagents/trainers/torch/encoders.py

             kernel_init=Initialization.KaimingHeNormal,
             kernel_gain=1.0,
         )
-        self.sequential = nn.Sequential(*self.layers)
+        self.sequential = nn.Sequential(*layers)
 
     def forward(self, visual_obs):
         batch_size = visual_obs.shape[0]

ml-agents/mlagents/trainers/trainer_controller.py

 from mlagents.trainers.agent_processor import AgentManager
 from mlagents.tf_utils.globals import get_rank
 
+try:
+    import torch
+except ModuleNotFoundError:
+    torch = None  # type: ignore
+
 
 class TrainerController:
     def __init__(
         self.kill_trainers = False
         np.random.seed(training_seed)
         tf.set_random_seed(training_seed)
+        if torch is not None:
+            torch.manual_seed(training_seed)
         self.rank = get_rank()
 
     @timed